1. Field of the Invention
The present invention relates generally to medical testing devices of the type having a keypad for providing instructions and data to the device and more particularly to methods and apparatus for controlling such devices.
2. Description of the Related Art
A variety of medical devices used to obtain patient data include a keypad for providing instructions and data to the device. One such device is a cardiograph which is connected to a patient via a plurality of electrodes. The cardiograph electrodes detect electrical activity resulting from the patient's heart across different selected pairs of the electrodes thereby providing ECG waveforms to the cardiograph. A typical cardiograph is equipped with a memory for storing patient waveforms, a screen for displaying the waveforms as they occur and a printer for printing the waveforms on paper.
Such cardiographs also typically include a keypad which an operator uses to perform a number of different functions. At each cardiographic recording session, patient data including the patient's name, room number (if in a hospital) and patient ID number may be entered. Data such as age, race, weight, blood pressure, operator identity, patient medication, etc. may also be entered. The name of the physician requesting the cardiographic examination also is usually included.
In addition to keying in data such as that described above, cardiograph operators must provide instructions via the keypad which control the cardiograph during the process of obtaining and analyzing ECG waveforms. For example, instructions must be provided concerning which pairs of electrodes, referred to as leads, are selected to be recorded. The duration of the recorded waveform must also be selected. Sometimes data is obtained for preselected periods alternating with a period during which no data is recorded in order to observe changes in the waveform over time.
Often different physicians provide standing instructions concerning configuration of the cardiograph for substantially all cardiographic recording sessions, e.g., duration of recording, selection of leads for recording, the order in which the different leads are recorded, etc. Thus, an operator of the cardiograph may provide some of the instructions to configure the cardiograph based on the requesting physicians standing orders.
Cardiographic recording is typically done in a hospital by an ECG technician who uses a cardiograph mounted on a cart. The technician typically begins a round by obtaining a list of patients, their room numbers and the physician requesting each cardiogram. The list may include information concerning the time of day when the session is to occur and the type of data, e.g., which leads are to be recorded, etc., that the requesting physician would like. The technician then takes the list and the cardiograph and proceeds to the first room. Once there, the technician connects the electrodes to the patient and begins keying information into the cardiograph via the keypad. This information includes patient identifying data such as that described above.
Thereafter, the technician configures the cardiograph with operating instructions which cause it to take selected leads for selected durations as described above. As mentioned above, some of the instructions provided by the technician via the keypad may not appear on the list of patients and related instructions but rather may be based upon standing orders issued by the requesting physician. Once complete, the technician disconnects the electrodes and takes the cardiograph to the next patient for the next recording session.
The main cause of error in obtaining cardiographic data as described above results from mistakes made by the technician when patient data and cardiograph configuration and control data is entered by the technician via the keypad. Such mistakes result in typographical errors in the data associated with the particular cardiogram and may even result in misidentification of a patient as a result of an error in entry of a room number or patient identification number. Similarly, when the keypad is used to provide cardiograph configuration and control commands, errors can result in acquiring data other than that requested.
It would be desirable to eliminate or substantially reduce entry of patient data and configuration and control commands to devices, such as a cardiograph, which obtain and analyze data from a patient.